Well slip assembly and hook wall anchor for a pumping string in a well casing



Sept. 29, 1964 c. P. HOWE 3,150,719

wan. SLIP ASSEMBLY AND HOOK WALL ANCHOR FOR A PUMPING STRING IN A WELL CASING Filed Jan. 30, 1963 2 Sheets-Sheet 1 4 l l i 7 V /6 I Z 7 INVENTOR Char/es P Howe WWW ATTORNEY Sept. 29, 1964 c. P. HOWE 3,150,719

WELL SLIP ASSEMBLY AND HOOK WALL ANCHOR FOR A PUMPING-STRING IN A WELL CASING Filed Jan. 50, 1963 2 Sheets-Sheet 2 INVENTOR LL Char/es F. Ho e m A, A

ATTORNEY United States Patent Ofiiice 3,150,719 Patented Sept. 29, 1964 3,150,719 WELL SLEEP ASSEMBLY AND 1100K WALL ANCHOR FOR A. PING STRENG IN A WELL CASING Charles P. Howe, 226 E. Elm St., R0. Box 49, Albion, Iil. Filed Jan. 3th, 1%3, Ser. No. 254,978 4 Claims. (Cl. 166-217) This invention relates to a well slip assembly and to a hook wall assembly for a pumping string in a well casing and has for an object to provide an improved well slip assembly and also to an improved hook wall assembly for a pumping string in a well casing.

A further object of this invention is to provide a well slip assembly made in one piece thereby not only facilitating its manufacture, but greatly facilitating its use in a hook wall anchor for releasably anchoring a pumping string within a well casing so that it will support the weight of the pumping string therebelow, and which may readily be released from anchoring cooperation with the well casing when it is desired to remove the pumping string from the bottom of the well, and wherein the anchor is released from the well casing before the weight of the pumping string therebelow is picked up, thus facilitating the lifting of the pumping string and its removal from the well casing.

Still a further object of this invention is to provide an improved well slip assembly wherein there are a plurality of slip hooks, each integrally connected by a slip stern substantially narrower than the slip hook head, with the slip stems extending integrally from a single integral collar in the general direction of the axis of the integral collar.

Still a further object of this invention is to provide a well slip assembly and hook anchor particularly useful in supporting the weight of the pumping string hanging therebelow and more particularly for hooking the pump ing string to the well casing when the mud anchor is set at the bottom of the well and thus prevent the mud anchor from working down through the sand, shale and cavings during pumping operation which might otherwise cause the pump to settle further down and pull the packing loose and thus cause a breakdown of the pumping operation necessitating a pulling and servicing job.

Still a further object of this invention is to provide an improved well slip assembly and hook wall anchor, particularly useful in multiple completion wells, as well as in other types of wells, in preventing excessive weight loads on productioon equipment in deep wells and to assist in maintaining a controlled hydrostatic pressure and water flow control.

With the above and related objects in view, this invention consists in the details of construction and combination of parts, as will be more fully understood from the following description, when read in conjunction with the accompanying drawing in which:

FIG. 1 is an elevational view of the well slip assembly of this invention used as a hook wall anchor in operative position in a well casing.

FIG. 2 is an enlarged detailed section in wall hook anchoring position.

FIG. 3 is a sectional view on line 33 of FIG. 2, showing the slip hook heads in anchored position.

FIG. 4 is a sectional view on line 44 of FIG. 2.

FIG. 5 is a partly sectional and partly elevational view of the slip well assembly on the pumping string in nonanchoring position.

FIG. 6 is a continuation of the bottom of FIG. 5 on line A-A.

There is shown at it the well slip assembly of this invention, which is used as a wall hook anchor in combination with a pumping string 12 supporting a cooperating mandrel 14 within a well casing 16.

The well slip assembly ll? per se consists of an integral collar 13 of suitable circumference from which integrally extends a plurality, here shown as four, of slip stems 20 spaced from each other by spaces 22, the width of the spaces 22 being greater than the circumferential Width of the stem 2% and at the upper end of each slip Zii there is provided a slip hook head 24.

Each hook slip head 24 is spaced from each adjacent hook head 24 by a comparatively narrow space 26 sufficient to permit the hook heads 24 to approach each other when in non-holding position. As will be apparent from FIGS. 3 and 4, the slip stems 2t) and hook heads 24 are annular in cross section, generally having the same circumference, when in relaxed non-holding position, as the slip assembly collar 18.

On the inner surface of each hook head 24, a tapered surface 23 is provided from a point 39 intermediate the attached end 32 and free end 34 of each hook head 24, this tapered surface 28 tapering outwardly. The outer surface of each hook head 24 is provided with a plurality of parallel circumferential hook ridges 36 shaped approximately as shown. It will be observed that each book ridge 36 has a long surface 38 approximately at right angles with a short surface 40, thus providing a sharp edge 32 which provides the gripping hook portion thereof in cooperating with the well casing 15 when the hook head 24 is forced or wedged into contact therewith by a complementary tapered conical surface 44 on the mandrel 14.

In operation, when the mandrel 14 has its tapered conical surface 44 pushed downwardly, in a manner hereinafter described, into wedging action within the hook heads 24, the hook heads 24 are wedged outwardly into anchoring position with the well casing 16, as clearly illustrated in FIG. 2, as well as in FIG. 1 and FIG. 3.

The mandrel 14 is connected in a conventional manner by means of a left hand safety coupling 46 at the top thereof to a pumping string 12 of conventional construction above which there may be located the usual pump head and packer assembly and through which there extends the pumping rod 69 connected thereabove to the sucker rod, the same being of conventional details, one illustration of which is shown in applicants prior patents, numbered 2,674,198 and 2,674,200.

Depending from the mandrel 14 is an assembly tube Eli, the assembly tube Bil extending slidably down through the packing assembly 52 with its packing 54, the assembly tube 59 terminating in an enlarged shouldered end 56, having a shoulder 58, the shoulder 58 being of a size to abut against the bottom of the packing assembly 52, as shown in FIG. 6, while the shouldered end 56 can slide down freely in an assembly barrel Gil secured to packing assembly 52.

As will be observed in FIGS. 1 and 5, the slip assembly 10 slides freely on the assembly tube 56 between the bottom of the tapered end 44 of mandrel 14 and the top of packing assembly 52.

An adapter 64 connects the bottom of the assembly barrel 6% to a coupling 62 from which depends the pumping barrel 66 within which the pump piston with its usual packing it? and pump valves (not shown) operates. Secured at the bottom of the pumping barrel 66 is the perforated mud anchor '72 through which oil from the pay zone 74 may enter and be subject to the action of the pump piston 63 within the pumping barrel 66. Obviously, in a multi-completion well, there may be additional pay zones located above the bottom pay zone 74. In such case, the well casing will be suitably perforated as at '76 to allow the oil or fluid from the additional pay Zones to enter into and through the well casing 16 and through the mud anchor 72 into the pump barrel 66 to be subject to the action of the pump piston 63. In such multi-eom plction wells, the packing assembly (not shown) is, of course, set above the top well casing perforations 7 6 while the pump 68 must be adjacent the bottom of the lower pay zone to be produced. This eliminates the possibility of the lower zones thiefing oil produced by the upper zones. The hook wall provided by the well slip assembly is attached to the bottom of the head assembly by the left hand safety coupling 4-6. As much tubing as is necessary may be run between the packing assembly 52 and the pump therebelow, as apparent from FIGS. 5, 6 and 7.

This invention serves to prevent excessive weight loads on production equipment in deep wells. Some deep oil wells are skimmed from a point up the hole to prevent excessive weight loads on the production equipment. When this is accomplished with conventional equipment, water accumulates in the bottom of the well, restricting the production. When this restriction of production occurs, it becomes necessary to pull the well and swab or hail the water from the well bore. By running tubing to the bottom and setting the hook wall at the desired pump level, this pump can be run on rods with a special seal and prevent excessive weight loads on the production equipment and also completely eliminate the accumulation of water in the bottom of the well.

This equipment, as described also serves to maintain a controlled hydrostatic pressure in water floods. In some water flood projects, it is necessary to maintain certain hydrostatic back pressure on the formation to force the water through the less permeable portion of the sand, or to prevent it from channeling through previously flooded areas of the reservoir.

With this pumping equipment, this is accomplished by suspending the tubing from the hook wall which is set at a calculated point up the hole to maintain the desired back pressure. The pump is then run on the rods and sealed to the tubing with a seal at that point.

This invention has thus provided both an improved slip assembly and an improved hook wall anchor utilizing such slip assembly and useable in solving different well problems.

Although this invention has been described in considerable detail, such description is intended as being illustrative rather than limiting, since the invention may be variously embodied, and the scope of the invention is to be determined as claimed.

Having thus set forth and disclosed the nature of this invention, what is claimed is:

1. A hook wall anchor for a pumping string in a Well casing comprising a well slip assembly collar, a plurality of circumferentially spaced apart slip stems integrally extending at one end from said collar in the general direction of the axis of said collar, and a slip hook head integrally extending from the other end of said slip stem, the inner surface of each said hook head tapering toward its unattached end, in combination with a mandrel mounted in the pumping string adjacent to the tapered ends of each said slip hook heads, said mandrel being externally tapered complementary to the internal taper on said hook heads, said mandrel being manipulable to insert its externally tapered surface against the internal tapered surfaces of said slip hook heads to wedge said slip hook heads into anchoring position against the inner surface of the well casing, and means for manipulating said mandrel and said slip hook heads into and out of anchoring position comprising a tubing string to the bottom of which said wedging mandrel is secured, an assembly tube secured to and depending from said mandrel, a packing and a packing assembly through which said assembly tube slidably extends, said slip assembly sliding freely on said assembly tube and resting on said packing assembly, a circumferential shoulder on said assembly tube extending outwardly beneath said packing assembly supporting said packing assembly when lifted thereagainst, an assembly barrel secured to and depending from said packing assembly, said shouldered end of said assembly tube sliding freely in said assembly barrel, and a mud anchor secured to and depending from said assembly barrel, whereby the pumping string may be lowered into said well casing until said mud anchor rests on the well bottom, then the pumping string being further lowered, forces tl e tapered mandrel surfaces into wedging cooperation with said slip assembly resting on said packing assembly to anchor the slip assembly to the well casing and prevent the mud anchor from working substantially downwardly through the well bottom during pumping operations, and whereby the pumping string may lift the mandrel out of the slip assembly before the mud anchor is raised off the well bottom when removing the pumping string.

2. The hook wall anchor of claim 1, the tapering of the inner surface of each said hook head extending from a point intermediate its ends to its unattached end.

3. A hook wall anchor for a pumping string in a well casing comprising a well slip assembly collar, a plurality of circumfcrentially spaced apart slip stems integrally extending at one end from said collar in the general direction of the axis of said collar, and a slip hook head integrally extending from the other end of each said slip stem, the inner surface of each said hook head tapering toward its unattached end, the circumferential width of each slip stem being substantially less than the Width of the space between adjacent stems, and also less than the circumferential width of the said hook head extending therefrom, the circumferential width of each hook head being substantially greater than the width of the space between adjacent heads, and a plurality of hook ridges on the outer surface of each said hook head, said hook ridges extending circumferentially and parallel to each other on each said hook head, in combination with a mandrel mounted in the pumping string adjacent to the tapered ends of each said slip hook heads, said mandrel being externally tapered complementary to the internal taper on said hook heads, said mandrel being manipulable to insert its externally tapered surface against the internal tapered surfaces of said slip hook heads to wedge said slip hook heads into anchoring position against the inner surface of the well casing, and means for manipulating said mandrel and said slip hook heads into and out of anchoring position comprising a tubing string to the bottom of which said wedging mandrel is secured, an assembly tube secured to and depending from said mandrel, a packing and a packing assembly through which said assembly tube slidably extends, said slip assembly sliding freely on said assembly tube and resting on said packing assembly, a circumferential shoulder on said assembly tube extending outwardly beneath said packing assembly supporting said packing assembly when lifted thereagainst, an assembly barrel secured to and depending from said packing assembly, said shouldered end of said assembly tube sliding freely in said assembly barrel, and a mud anchor secured to and depending from said assembly barrel, whereby the pumping string may be lowered into said well casing until said mud anchor rests on the well bottom, then the pumping string being further lowered,

forces the tapered mandrel surfaces into Wedging cooperation with said slip assembly resting on said packing assembly to anchor the slip assembly to the well casing and prevent the mud anchor from working substantially downwardly through the well bottom during pumping operations, and whereby the pumping string may lift the mandrel out of the slip assembly before the mud anchor is raised off the well bottom when removing the pumping string.

4. The hook wall anchor of claim 3, the tapering of 10 the inner surface of each said hook head extending from a point intermediate its ends to its attached end.

References Cited in the file of this patent UNITED STATES PATENTS 2,345,888 Scott Apr. 4, 1944 2,708,001 Reed May 10, 1955 2,982,355 Rodgers May 2, 1961 3,097,697 States July 16, 1963 

1. A HOOK WALL ANCHOR FOR A PUMPING STRING IN A WALL CASING COMPRISING A WELL SLIP ASSEMBLY COLLAR, A PLURALITY OF CIRCUMFERENTIALLY SPACED APART SLIP STEMS INTEGRALLY EXTENDING AT ONE END FROM SAID COLLAR IN THE GENERAL DIRECTION OF THE AXIS OF SAID COLLAR, AND A SLIP HOOK HEAD INTEGRALLY EXTENDING FROM THE OTHER END OF SAID SLIP STEM, THE INNER SURFACE OF EACH SAID HOOK HEAD TAPERING TOWARD ITS UNATTACHED END, IN COMBINATION WITH A MANDREL MOUNTED IN THE PUMPING STRING ADJACENT TO THE TAPERED ENDS OF EACH SAID SLIP HOOK HEADS, SAID MANDREL BEING EXTERNALLY TAPERED COMPLEMENTARY TO THE INTERNAL TAPER ON SAID HOOK HEADS, SAID MANDREL BEING MANIPULABLE TO INSERT ITS EXTERNALLY TAPERED SURFACE AGAINST THE INTERNAL TAPERED SURFACES OF SAID SLIP HOOK HEADS TO WEDGE SAID SLIP HOOK HEADS INTO ANCHORING POSITION AGAINST THE INNER SURFACE OF THE WELL CASING, AND MEANS FOR MANIPULATING SAID MANDREL AND SAID SLIP HOOK HEADS INTO AND OUT OF ANCHORING POSITION COMPRISING A TUBING STRING TO THE BOTTOM OF WHICH SAID WEDGING MANDREL IS SECURED, AN ASSEMBLY TUBE SECURED TO AND DEPENDING FROM SAID MANDREL, A PACKING AND A PACKING ASSEMBLY THROUGH WHICH SAID ASSEMBLY TUBE SLIDABLY EXTENDS, SAID SLIP ASSEMBLY SLIDING FREELY ON SAID ASSEMBLY TUBE AND RESTING ON SAID PACKING ASSEMBLY, A CIRCUMFERENTIAL SHOULDER ON SAID ASSEMBLY TUBE EXTENDING OUTWARDLY BENEATH SAID PACKING ASSEMBLY SUPPORTING SAID PACKING ASSEMBLY WHEN LIFTED THEREAGAINST, AN ASSEMBLY BARREL SECURED TO AND DEPENDING FROM SAID PACKING ASSEMBLY, SAID SHOULDERED END OF SAID ASSEMBLY TUBE SLIDING FREELY IN SAID ASSEMBLY BARREL, AND A MUD ANCHOR SECURED TO AND DEPENDING FROM SAID ASSEMBLY BARREL, WHEREBY THE PUMPING STRING MAY BE LOWERED INTO SAID WELL CASING UNTIL SAID MUD ANCHOR RESTS ON THE WELL BOTTOM, THEN THE PUMPING STRING BEING FURTHER LOWERED, FORCES THE TAPERED MANDREL SURFACES INTO WEDGING COOPERATION WITH SAID SLIP ASSEMBLY RESTING ON SAID PACKING ASSEMBLY TO ANCHOR THE SLIP ASSEMBLY TO THE WELL CASING AND PREVENT THE MUD ANCHOR FROM WORKING SUBSTANTIALLY DOWNWARDLY THROUGH THE WELL BOTTOM DURING PUMPING OPERATIONS, AND WHEREBY THE PUMPING STRING MAY LIFT THE MANDREL OUT OF THE SLIP ASSEMBLY BEFORE THE MUD ANCHOR IS RAISED OFF THE WELL BOTTOM WHEN REMOVING THE PUMPING STRING. 